What is the best way to design freeform optical surfaces using computer-aided design (CAD)?

2 How to choose a CAD software for freeform optics?

When choosing a CAD software for freeform optics, there are many factors to consider. Accuracy and precision should be taken into account, as some CAD software can handle higher-order polynomial or spline-based surfaces, while others can only handle lower-order or spherical surfaces. The type and complexity of the surface is also important, as some CAD software can generate freeform surfaces based on predefined functions or templates, while others can allow you to create custom shapes or modify existing ones. Additionally, compatibility and interoperability with optical analysis and simulation software, as well as fabrication and testing methods, should be considered. Finally, the ease of use and learning curve of the CAD software should be taken into account; some CAD software can have intuitive and user-friendly interfaces, while others can have steep and complicated learning curves.

3 How to create a freeform surface in CAD?

Creating a freeform surface in CAD can vary depending on the software you use, but the general process involves defining the basic parameters of your surface, choosing a method for generating or creating it, adjusting parameters for the desired shape and curvature, and checking the quality and performance of your freeform surface. You can use the CAD software's tools and commands to manipulate and modify your freeform surface, such as scaling, rotating, moving, or twisting. Additionally, you can analyze and evaluate your freeform surface with tools like measuring, inspecting, or visualizing. In summary, creating a freeform surface involves defining parameters, choosing a method, adjusting parameters for desired shape and curvature, and checking the quality and performance.

4 How to optimize a freeform surface in CAD?

Once you have created a freeform surface in CAD, you may want to optimize it further to improve its optical performance and functionality. You can use the CAD software's tools and commands, such as applying constraints or objectives to your freeform surface, running an optimization algorithm or solver to find the optimal parameters, and comparing and selecting the best solution based on criteria or metrics that you have defined. For example, you can minimize the root mean square (RMS) error, maximize the modulation transfer function (MTF), or achieve a specific focal length or field of view. Additionally, optimization algorithms such as gradient descent, genetic algorithm, or simulated annealing can be used to find the best solution.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?